Why should he have to apologise?
Have people who voted Tory in 1979 applogised for voting Tory?

I'm not apologising for voting Leave and no, I don't believe that there's a colony of unicorns living at the bottom of my garden and I'm not stupid either.
He's probably frustrated at the treason Parliament are carrying out and getting away with and he can't legally do anything about it or punish them for it either.